#include<stdio.h>

int main()
{
    int steps,i;
    int upcount=0;
    int downcount =0;
    int valley=0;
    int valley_count=0;
    int level_track;
    int level = 0;
    scanf("%d",&steps);
    char stair[steps];
    for(i=0;i<steps;i++)
    {
        scanf("%c",&stair[i]);
        if(stair[i]=='U')
        {
            upcount++;
            level_track=level;
            level++;
        }
        if(stair[i]=='D'){
            downcount++;
            level_track=level;
            level--;
        }
        if(level<0 && level_track==0){
            valley=1;
        }
        else{
            valley=0;
        }
        if(upcount<downcount && valley == 1){
            valley_count++;
        }
    }
    printf("%d", valley_count);
    return 0;
}